Even then it would be a waste of money. Why? Because I can pickup an auxiliary car charger for about $25 when most FM transmission+charger units are $40 or more. Why spend almost double the money for something that produces terrible quality? So I stand by what I said: it would be a waste of money to purchase an FM transmission unit. This is especially true since the iPod's headphone output port (directly hooked up to an aux input) will sound world's better than ANY FM transmitter (that is not a matter of opinion either, that is a fact).
Just use the iPod's headphone output port until an auxiliary+charger unit can be purchased. It makes no sense to use an FM transmitter when the OP has an auxiliary connection in their car.